| 摘要 |
PROBLEM TO BE SOLVED: To discriminate failures at multiple portions with one current detector by providing a first main circuit electric wire connected to an inverter from a capacitor and a second main circuit electric wire connected to a converter from the capacitor, and providing the current detector between the capacitor and the first and second main circuit electric wires. SOLUTION: This control device is provided with a current detector 31 synthesizing the current flowing from a smoothing capacitor 5 to an inverter 6 and the current flowing from the capacitor 5 to a converter 4 in opposite polarities for detection. At the time of a normal operation, a control circuit 16 turns on a main contactor 3 by the start command of an elevator, a three-phase AC power source 1 is connected to the converter 4 to charge the capacitor 5, and the inverter 6 is controlled to drive a motor 7. When the inverter 6 fails, for example, the electric power charged in the capacitor 5 flows out toward the inverter 6, the short circuit current is increased, this current is detected by the current detector 31, and a safety circuit recognizes the failure of the inverter 6. |
